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Problems with FFT and IFFT
From: |
Sascha Berkenkamp |
Subject: |
Problems with FFT and IFFT |
Date: |
Tue, 28 Feb 2006 16:54:11 +0100 |
User-agent: |
Mutt/1.5.9i |
Hi,
I've got a simple problem with the FFT and the IFFT function.
I have got one function from matlab with both functions in it. But I
will not get the same results. So I started with testing on simple
task.
I have got a signal, transform it to the frequenz-domain and then I
transform it back to the time-domain.
Generally after transforming the signal shout be the same than the
input signal.
So my input signal (x) has no imag-part. So my retransformed signal
shoud have no imag-part, too.
fs = 0:0.1:10;
x = sin(2*pi*fs);
real(x)
imag(x)
X = fft(x);
x2 = ifft(X);
real(x)
imag(x)
But in my octave version (octave 2.1.72 from debian etch) the
imag-part of the retransformed signal is not zero.
When I put the code into matlab, everything is okay: no imag-part
after retransforming into the time-domain.
Sascha
--
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-------------------------------------------------------------
- Problems with FFT and IFFT,
Sascha Berkenkamp <=
- Re: Problems with FFT and IFFT, Keith Goodman, 2006/02/28
- Re: Problems with FFT and IFFT, Keith Goodman, 2006/02/28
- Re: Problems with FFT and IFFT, John W. Eaton, 2006/02/28
- Re: Problems with FFT and IFFT, Dmitri A. Sergatskov, 2006/02/28
- Re: Problems with FFT and IFFT, Sascha Berkenkamp, 2006/02/28
- Re: Problems with FFT and IFFT, John W. Eaton, 2006/02/28
- Re: Problems with FFT and IFFT, Joe Koski, 2006/02/28
- Re: Problems with FFT and IFFT, Quentin Spencer, 2006/02/28
- Re: Problems with FFT and IFFT, Joe Koski, 2006/02/28
- Re: Problems with FFT and IFFT, Bill Denney, 2006/02/28